Safety-valve



(NoModeL) i W. E. GRANGER.

SAFETY VALVE. No. 326,904. Patented Sept. 22, 1885.

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XVILLIAM E. GRANGER, OF SPRINGFIELD, MASSACHUSETTS.

SAFETY-VALVE.

SPECIFICATION forming part of Letters Patent No. 326,904,.diltedSeptember 22, 1885.

Application filed May 18, 1885. (No model.)

To all whmn it may concern:

Be it known that I, WM. E. GRANGER, a citizen of the United States,residing at Springfield, in the county of Hampden and State ofMassachusetts, have invented new and useful Improvements in SteamSafety-Valves, of which the following is a specification.

This invention relates to improvements in steam safety-valves, theobject being to provide improved attachments for certain classes of saidvalves, whereby when the parts which hold the valve against thesteam-pressure become accidentally broken and the valve is blown out,the aperture through which the steam escapes closes automatically,thereby, in the case of a locomotive upset by an accident, preventingthe escape of steam and hot water therefrom by which persons may bescalded.

In the drawings forming part of this specification, Figure 1 shows avertical section of aportion of the dome of alocomotive having appliedthereto a steam safety-valve embodying my improvements. Fig. 2 is aperspective View of the valve proper of the safetyvalve, and theautomatically-acting valve. Fig. 3 is a perspective view of thevalve-seat, and of the cage for the said automaticallyclosing valve.

In the drawings, B indicates a portion of the dome of a locomotive orother boiler. The valve parts shown in the drawings, excepting thosepertaining to the within-described improvements, are substantially thoseconstituting what is known as the Richard son safety-valve, which waspatented J anuary 19, 1869, No. 85,963, to which patent, for a specificdescription of the safety-valve, reference may be had.

The valve 0, the form of which is fully shown in Fig. 2, has its seatupon that part of the circular plate or flange a surrounding the upperopen end of the cylindrical valvechamber a, the latter constituting apart of the plate a. A second valveseat, e, is formed in the lower endof the chamber a, and said end is screw-threaded to providefor screwingthe valve-cagefthereon in theposition shown in Fig. 1.

The valve 0 has a square socket, d, in its lower end to receive thesquared end d of the shank d of the lower valve, 0. The square socketand shank connection between the valves 0 and 6 provides for turning thetwo valves one by the other, for freeing and cleaning them. Butfor theaction of valve 6 to antomatically shut off the steam, as hereinafterset forth, said connection between the two valves is not essential; butthe shank (I may have a round end entering a suitable socket in thevalve 0.

The valve eis held in its proper position at the end of chamber a by thecage f, directly under the seat 6' at the lower end of said chamber, theend of the shank d of said valve entering the socket d in valve 0, andextending to near the end of the socket, so that the movement of valve 0toward its seat must be controlled by the movement of valve 0 in thesame direction.

The plate a is firmly bolted to the dome B, as shown, the posts b b ofthe spring-yoke A being attached to said plate.

A guide-bolt is screwed into valve 0 and passes through a crossbarsecured to the upper ends of the posts I) b, and the usual springsurrounds said bolt,whose ends have a bearing against valve 0 and theunder side of said cross-bar, whereby said valve is held to its seat.

The operation of my improvements is as follows: The valve 6 cannot moveagainst its seat 6 while the yoke parts A, including the valve-spring,are intact, and said spring holds valve 6 on or very near its seat; butvalve 6 may, with valve 0, have the limited movement which the latterhas when steam is blowing oft. But when by accident the parts above thedome B, which guide and hold valve 0 against the steam-pressure of theboiler, are broken ofi' and valve 0 is blown from its seat and away fromthe shank d, the valve e,properly guided by the cage f,is immediatelydriven against its seat 6, stopping all escape of steam or water, andpreventing persons on or near the engine from being scalded thereby inthe manner that they are when, under ordinary conditions, nothingprevents the steam and water from escaping when said valve 0 is blownaway.

The cage f serves to retain the valve 6 in proper position when thepressure on the boiler ceases, so that a new valve 0 can be placed inthe chamber a, and brought into proper connection with the valve 6, asbefore.

The employment of valve 6 and the cagef is not necessarily limited tothe precise construction of safety-valve herein shown, but they may beused in connection with any safety-valve so constructed that itspressureresisting valve, answering in function to the valve 0, iscapable of being blown away from the boiler, as above described.

What I claim as my invention is- 1. In combination witha safety-valveopening outwardly, and mechanism to permit the same to openautomatically under pressure,

an interior valve-seat and valve, the valve be ing loosely connected tothe safety-valve and I 5 held off its seat by said safety-valve whenclosed. substantially asdescribed.

2. The combination, with the boiler, valveseat, and spring-pressed valve0, of the valve 6 in a cage in the boiler, said valve having a 20polygonal stem, d, entering acorresponding aperture in the body of valve0, as set forth.

W. E; GRANGER. Witnesses:

HENRY KNOX, WM. H. CHAPIN.

